The world transportation system is using natural resources at a high rate. That is, conventional drive systems using internal combustion engines rely on the use of natural resources, such as fossil fuels for power. However, the supply of fossil fuels is limited and world supplies are increasingly being stretched to support world demand. In addition, byproducts of these conventional drive systems cause unhealthy pollution. Moreover, the price of fossil fuels, such as gasoline, is increasingly becoming cost prohibitive. In the interest of saving natural resources, decreasing pollution, and saving costs, consumer demand for vehicles (e.g., automobiles) with increased fuel efficiency is becoming more prevalent.
A conventional solution is the hybrid vehicle in which internal combustion engines are tightly integrated with electric propulsion systems. Specifically, the conventional hybrid vehicle integrates two separate energy sources to power a single drive control system. Prior Art FIG. 1 illustrates a conventional hybrid vehicle 100 in which the internal combustion engine 110 and an electric drive system 120 is integrated in a drive control system. As shown in Prior Art FIG. 1, the conventional hybrid vehicle uses energy from either the internal combustion engine 110 or the electric drive system 120, separately or in combination, to drive a single set of wheels 130. However, the design engineering required to tightly integrate the internal combustion engine and the electric drive system is complex and could delay the introduction of new hybrid vehicles by a number of years. In addition, existing conventional hybrid drive vehicles having very tightly integrated internal combustion engine systems and electric drive systems have been very difficult to extend beyond a very few vehicle designs.